ul li {
    margin: 0;
    padding: 0;
    list-style: none;
}
#app {
    width: 600px;
    height: 400px;
    margin: 0 auto;
    border: 1px solid #ccc;
}
.tab-tilte{
    width: 90%;
}
.tab-tilte li{
    float: left;
    width: 25%;
    padding: 10px 0;
    text-align: center;
    background-color:#f4f4f4;
    cursor: pointer;
}
/* 点击对应的标题添加对应的背景颜色 */
.tab-tilte .active{
    background-color: #09f;
    color: #fff;
}
/* .tab-content div{
    float: left;
    width: 25%;
    line-height: 100px;
    text-align: center;
} */